Heretofore, difficulties have been encountered in the separation of links of disintergating ammunition belts of some automatic weapons, such as automatic grenade launchers, particularily those weapons in which the individual links totally circumscribe the round and were delinked in the receiver rearwardly by the recoiling bolt.
The conventional feed tray mechanism, especially the feed pawl, was required to cope with the varying dynamic force loads of the remaining rounds linked in the belt, due both to feeding and belt surge, while attempting to feed individually each linked round to the firing chamber for firing thereof. The varying load forces produced by the moving belt, as well as the surge force loads of the moving belt were translated to the weapon and resulted in unpredictable dilatorious effects on the weapon firing rate and on its hit probability. It will be appreciated, also, that the firing rate and hit probability of the weapon were also adversely affected by the lessening of the belt load on the weapon, during sustained firing, due to weight reduction of the belt ammunition supply, e.g. as the belt load forces were reduced, because of reduction in ammunition supply, the weapon firing rate increased, affecting thereby weapon control and, thus, target hit probability.
Moreover, where the delinking is to occur in the receiver after the round is fired, the gunner, in the event of failure of the stripping operation or in the event only partial stripping of the link in the firing chamber occurs, causing the weapon to jam, is required to open the feed cover and remove the unstripped or partially stripped round from the receiver, after having first delinked the chambered round from the remainder of the belt, thereby presenting substantial safety hazards.
Furthermore, because the link design configuration is generally fixed before the feed tray design is begun, a link which encompasses totally the casing and must be stripped rearwardly toward the breech, severely limits the design parameters of a link stripping assembly slaved to the configuration of the link.
In addition, the requirement that the link perform an indexing function to center the round for delivery from the feed tray to the firing chamber position in the receiver imposes further limitations on the design of a stripper assembly capable of stripping the links in the feed tray prior to delivery to the firing chamber.
In prior art link design, the "pitch" between links was also a limiting factor in weapon design. For purposes hereof, "pitch" is defined as the distance between the vertical centerlines of two adjacent rounds linked together with the link connection therebetween under full extension without stress thereon. The pitch distance was instrumental in determining the wall thickness of the barrel of the prior art weapons. The barrel wall thickness was dictated by the distance, and, therefore, had to be sufficiently thin to permit feed of only one round into the firing chamber from the feed tray, even though the rounds were linked when one was fed into the firing chamber.